Cisterns are conventionally and commercially manufactured at a plant in one large monolithic structure normally requiring transportation by means of a large truck or the like to the location at which the cistern is to be installed. This transportation exposes the cistern to the hazards of breakage or damage while at the same time requiring heavy equipment for purposes of loading and unloading. Moreover, where such cisterns are cast as a one-piece unit, problems of stresses arise which sometimes result in inherent weaknesses. Certain proposals have been made for purposes of fabricating cisterns from sub-units or sub-assemblies which are transported as such to the location where they are to be installed. These techniques for various reasons have never found large commercial application.